1. Field of Invention
The invention pertains to trailers. More particularly, the invention applies to de-limbing trailers for removing limbs from trees. More particularly, the invention applies to extendable de-limbing trailers for removing limbs from trees having hydraulic lifters.
2. Prior Art
Trailers are known having two levels with the upper level holding a saw and the lower level holding a tree mover. Trailers having manually operated lifting logs are also well known.
3. General Discussion of the Invention
In the prior art these trailers having two levels for holding a loader with a de-limbing saw. These typically have a wheel level and a raise level as is taught by the present invention. The major benefit of the present invention when compared to the prior art lies in the fact that the present invention is more easily maneuverable while providing the same length as the prior art trailers by having an extendable upper section. An extendable lower section is also taught as an alternate embodiment.
In addition because the length of the space between the log handling device and the de-limber is also adjustable by virtue of the design described herein, the present invention allows for more complete and more efficient de-limbing and trimming of the logs.
It is important to note that in the field these large trailers which are used in the de-limbing process are very difficult to maneuver and providing the design which is more easily maneuverable has a number of time saving benefits.
Because there is in existence technology for diverting the flow of hydraulic fluid, and because limb handling device is run on a hydraulic system, no additional hydraulics are necessary in order to power this unit although they can be powered by a separate motor and a separate hydraulic fluid source.
Because of the nature of the device and the fact that it does not require a tremendous amount of speed in which to operate it may also work on a very low pressure hydraulic source so that the motors to drive it need not be large nor need it take a lot of hydraulic fluid in order to run the unit.
Novel leveling features are also important improvements taught herein, because the traditional method is to place a log and then manually level the supports over the log to support the unit. As the device sinks into soft ground or as the log that it rests on splinters the present invention can adjust the angle caused by this shifting or when the device is set up. This is an important safety feature.
Either by automatically adjusting the level or by adjusting it manually utilizing a reference level within or without the cab, the device is rendered safer because it is held level. This leveling may be automatic by having circuitry designed to run the hydraulic leveling legs to a level position.
When the device becomes sufficiently off level it can shut down the hydraulics. It may be designed to be biased to moving the legs to their shortest, longest or most mid-ranged extensions.
It should be noted that this is not an extensive re-leveling of the tractor since the supports are only one part of the total support of the system. Typically there are outriggers supporting the trailer where the handling device is located as well as the wheels under the trailer where the handling device is located.
The leveling, if automatic, may also control the outriggers to optimize the effect.
It should be noted in the present invention that the extendable part of the trailer described is an unsupported part of the trailer. It does support a fair amount of weight since there is a saw on the end of it and for this reason it has never been suggested that this type of technology be utilized on a trailer with this design and this purpose.
Since the leveling tends to change during the use of vehicle due to the supports or logs on which the supports are mounted either moving into the ground or cracking under strain the need to level the trailer can be important. Further, even with the initial set-up, this leveling technology provides a substantial improvement over current technology.
It is particularly helpful when dealing with scrape hardwood and some pines which have limbs close to the ground.
Two major innovations present with this invention are having a two landing-gear self leveling trailer and having travel trailer with a variable length between the tree lifter and the saw.
In addition since the trailer size is adjustable, it is easier to move a trailer in restricted spaces.
The invention works with less flexing because there is little flex in the rectangular tubing construction versus I-beam construction.
In addition the weight is better distributed because most log loaders are overweight on the trailer wheels and axles. This superior distribution is because the de-limber, which typically weighs six thousand pounds (6,000), can be moved forward. This transfers much of the load to the truck axles where it is needed and this is much safer. In some cases the truck is so light in preexisting models that if the xe2x80x9cPKGxe2x80x9d is required to stop on a grade it will require another vehicle to push or pull it to get it started.
There are three major lengths of trailers currently being manufactured because of the different log loader booms (the tree lifter arm 30) which are described as being a part of the invention. With this de-limbing trailer, the size of the trailer is adjustable and hence one trailer can be used for several different loader booms.
Additional improvements include having the variable length and leveling controlled by someone in a truck boom located on or near the trailer.
It is therefore an object of this invention to provide a trailer for trimming logs which may be reduced in length for positioning and extended in length in order to have a sufficient length in order to trim logs.
It is a further object of the invention in order to provide for a hydraulicly leveled trailer for de-limbing trees. It is a further object of the invention to provide a trailer with a saw to tree handling device length which is variable in order to allow more of the tree to be efficiently de-limbed.
These and other objects of the invention will become more clear from the drawings and the detailed embodiment in which like numbers correspond to like parts.
These and other objects and advantages of the invention will become better understood hereinafter from a consideration of the specification with reference to the accompanying drawings forming part thereof, and in which like numerals correspond to parts throughout the several views of the invention.